Variable spacing control



Feb. 19, 1963 CARTER 3,077,668

VARIABLE SPACING CONTROL Filed April 22, 1960 v 5 Sheets-Sheet 1 IN V EN TOR. 1701511 (29 122 Feb. 19, 1963 R. CARTER VARIABLE SPACING CONTROL 5 Sheets-Sheet 2 Filed April 22, 1960 IN VEN TOR. 21,615 61923122 firraeA/Eys I Feb. 19, 1963 R. CARTER VARIABLE SPACING CONTROL 5 SheetsSheet 3 Filed April 22, 1960 n R INVENTOR.

flrraz/viys I R. CARTER VARIABLE SPACING CONTROL Feb. 19, 1963 Filed April 22. 1960 5 Sheets -Sheet 4 INVENTOR. V )Z'aaw (123222 Feb. 19, 1963 R. CARTER VARIABLE SPACING CONTROL 5 Sheets-Sheet INVENTOR. 15 01111 (19 12222 Filed April 22, 1960 Hrraewz/ej United States Patent Ofilice 3,077,668 Fatented Feb. 19, 1963 3,677,668 VAREAEELE SPACENG (IGNTRGL Rollie Qarter, 2121 E. 2nd Sty, Tulsa, Okla. Filed Apr. 22, was, Filer. No. 24,647 Claims. ((ll. 33-81) This invention relates to a variable spacing control p rticularly adapted for the use of draftsmen or others who may be required to draw a plurality of parallel, evenly spaced lines for any purpose such as the lining of business forms, surface shading of drawings, cross hatching, drawing threads on a shaft, and other analogous purposes.

A primary object of the invention resides in the provision of a hand-operated mechanical device adapted for attachment to the underside of a drawing board or drafting table to carry a straight edge evenly along the top side of the board or table for the purpose of drawing accurate spaced parallel lines, designs, etc.

An additional object of the invention is the provision of such a device which is manually adjustable for variable spacing from hair lines to inches, which spacing may be repeated as many times as desired.

An additional object of the invention is the provision of such a device which is operated and controlled by a power head mechanism assembled on one end of the shaft, the shaft extending through the power head and supporting a carriage for holding a straight edge.

A further obiect of the invention is the provision of such a device wherein the shaft is provided with gears which rotate along a track having evenly spaced teeth which track extends the length of the drawing board or table.

A further object of the invention is the provision of such a device wherein the power or operating head is provided with a variable space control.

An additional object of the invention is the provision of a reset knob in the power head for rotating the shaft and its associated carriage back to the starting position.

Still another object of the invention is the provision of a brake in association with the power head which prevents rotation of the shaft between operations, holding the carriage and its associated straight edge in fixed position during the drawing of the lines therewith.

Still another object of the invention is the provision of such a device which may be designed for operation by either the left or right hand of the user, the device normally being operated and hereinafter described as operable by the left hand, so that the operator may employ his right hand for drawing lines.

Still another object of the invention is the provision of such a device which is sturdy and durable in construction, reliable and efficient in operation, and relatively simple and inexpensive to manufacture.

Still other objects reside in the combinations of elements, arrangements of parts, and features of construction, all as will be more fully described hereinafter and shown in the accompanying drawings wherein there is disclosed an illustrative embodiment of this inventive concept.

Still other objects will in part be obvious and in part be pointed out as the description of the invention proceeds.

In the drawings:

FIGURE 1 is a perspective view of one form of a device embodying the instant invention shown in association with a drawing board, parts thereof being broken away.

FEQURE 2 is an enlarged sectional view taken substantially along the line 2-2 of FIG. 1 as viewed in the direction indicated by the arrows.

FIGURE 3 is a top plan view of the apparatus of this invention with the drawing board disassociated therefrom.

FIGURE 4 is an exploded view partially in elevation and partially in section showing the component elements of the assembled power head.

FIGURE 5 is a sectional view taken substantially along the line 5-5 of FIG. 4 as viewed in the direction in dicated by the arrows.

FIGURE 6 is a sectional view taken substantially along the line 6-6 of FIG. 4 as viewed in the direction indicated by the arrows.

FIGURE 7 is a sectional View taken substantially along the line '7-7 of FIG. 4 as viewed in the direction indicated by the arrows.

FIGURE 8 is an exploded perspective View showing the component parts of the power head with the shaft removed, and

FIGURE 9 is an enlarged fragmentary detail sectional view taken along the line 99 of FIG. 5 as viewed in the direction indicated by the arrows.

Similar reference characters refer to similar parts throughout the several views of the drawing.

Having reference now to the drawing in detail, there is shown at 10 a drawing board of any desired conventional type, to which the apparatus of the instant invention is adapted to be secured.

The device of the instant invention includes a carriage which is comprised of a pair of oppositely disposed complementary frame members 11, each of which includes an elongated channel portion 112, having a depending horizontal flange 13, the horizontal portion being provided with enlarged plates 14 at each end, which plates are adapted to be attached as by means of screws 15 to the underside of drawing board 10.

Each plate 14 carries a depending shaft 16, which terminates at its lower end in a collar or socket 17, the sockets 17 at opposite ends of each frame member being in confronting relation. Threaded shafts 18 extend between the confronting sockets of each frame member, and serve as tracks for a pair of worm gears 2-0, which are mounted on opposite ends of a rotatable shaft 21, and secured in position by means of collars 22 and set screws 23 (see FIG. 2). One end 24 of shaft 21 is journalled in a ball bearing assembly 25, which is secured in a housing 25- which is fixedly secured to a movable plate 27, the end 24 being secured rotatably in the bearing assembly 25 by means of oppositely disposed collars 28 and secured in position by set screws 28. The other end 36 of shaft 21 extends through a bearing assembly 31, contained in a housing I52 which is secured to an opposite movable plate 33, the shaft being held in position by means of a collar 34 and set screw 34'. The end 30 of shaft 21 extends into a power head assembly generally indicated at 35 and to be more fully described hereinafter.

The lower portions of plates 27 and 33 are secured in alignment by spaced parallel rods 36, the ends of which seat in sockets 3'7 suitably mounted on the inner sides of both plates 27 and 33. Each plate 27 and 33 is provided with an upwardly extending portion 38 and 39, respectively, to the inner sides of which are secured confronting U-shaped blocks 30 and 41, respectively, which are apertured to receive set screws and 43. The set screws 42 and 43 serve to hold in position L-shaped bracket members id and 25, which brackets include horizontal flanges 4d and 47 which have dove-tailed grooves therein. The dove-tailed rooves are adapted for the reception of corresponding dove-tailed blocks 48 and 49 which are secured on opposite ends of a straight edge or rule 50. Set screws 51 and 52 serve clampingly to hold the blocks 43 and 49 in relative adjusted position within the associated flanges 46 and 4'7, for the initial alignment of the straight edge with the edge of the board, or other calibrating device.

Guide rollers 55 are carried by the inner side of each aovzses of plates 27 and 33 and mounted on stub axles 56, the peripheries of the guide rollers 55 being grooved to ride along the underside of the flanges 13 and serve as aligning guides.

Manual adjusting knobs 57 are provided at one end of each of threaded shafts or worms 18 in order to permit minute adjustment thereof.

From the foregoing it will now be readily apparent that when the shaft 21 is rotated through the power head assembly 35 in a manner to be more fully described hereinafter rotation of the worm gears 26 on their associated worms 18 will effect movement of the plates 27 and 33 along the frame members 11, which movement will in turn be imparted to the straight edge or rule Having reference now to the power head assembly 35, as best shown in FIGS. 4 to 8, inclusive, the shaft 21 extends through an opening 60 (see FIG. 8) in plate 33 and terminates at its outer end in a hand knob 61, which is fixedly secured thereto by means of a screw 62. A supporting bracket 63 is secured in any desired manner as by screws to the lower portion of plate 33 and carries at its end an upright apertured plate 64, the aperture being indicated at 65, and through which the shaft 21 extends. Between the plate 64 and the inner flange 66 of operating knob 61 is a brake assembly, which includes a brake wheel 67, provided with a collar 63 through which extend set screws 69 for securing the Wheel 67 fixedly to the shaft 21. The brake Wheel 67 includes a flange 67' (FIG. 4), against which are adapted to engage the outer arcuate faces of a pair of opposed brake shoes 70. Each brake shoe is provided with upper and lower transverse guide slots 71, through which are extended machine screws 72 which secure the brake shoe 70 to the support plate 64, the arrangements being such that the shoes may slide laterally. The shoes are normally biased into engagement with the inner side of flange 67 by means of springs 73.

Each brake shoe is provided with a yoke '74 forming a cam slot, in which a cam 75 may be rotated to retract the brake shoes 70 from contact with the interior of rim 67'.

As best shown in FIG. 9 the two yokes 74 are olfset relative to each other, and the cam 75 is provided with opposite flats 76, one of which is adapted to engage each yoke oppositely to permit retraction of the brake shoe 70 from the interior of flange 67.

On the other side of the plate 64 there is positioned a brake release wheel 78, which carries an extending brake release lever 79 having an operating handle 81) thereon. A hollow shaft 81 extends through the opening 65, and is secured to the cam 75, so that rotation of the brake release wheel serves to rotate the double cam 75 to release the brake shoes 70 from their engagement with flange 67. A spiral spring 82 is positioned interiorly of brake release wheel 78, and serves to rotate the brake release wheel 78 and its associated lever 79 back to start position, under circumstances to be more fully described hereinafter, or that is when the clutch assembly to be hereinafter described releases the brake release wheel. Spring 82 is fixed to plate 64 and to lever 79 so as to exert a restraining force on wheel 78 when said wheel is moved from its rest position. When the wheel is thus released, the brake shoes 70 engage again the interior of flange 67', and secure the shaft 21 against rotation, thus precluding the movement of the carriage and its associated straight edge 50 until the next operation is effected by the knob 61.

The power clutch assembly comprises a pair of substantially identical side plates 35, one of which carries a spacer flange 86, within which is positioned a cam lever spring 87 which is fixed to both lever 97 and to spacer lever 88, and which further engages a cam lever 88. The lever 88 is'connected to a pair of oppositely disposed double cams 89 which are carried by opposite ends of a tubular shaft 94) connected to the cam lever 83. The cams 3) are substantially identical in construction to the previously described cam '75, and serve to operate oppositely disposed pairs of clutch shoes 91, each clutch shoe being provided with an elongated slot at its upper and lower extremity, the slots being designated at 92, for the reception of suitable screws which hold the clutch plates in related assembly with the associated plates 85. Springs 94 serve normally to hold the clutch plates out of an engagement with flanges 95 which are carried respectively by the side of the brake wheel 78 and an oppositely positioned ring or power wheel 96. The clutch plates or discs 85 are provided with aligned operating handles 97.

A spacing control section is provided, and consists of a space control disc 98 which is provided with a guide block 99 through which extends a set screw 1%. An indicator point 161 is provided on the side of disc 98 towards end plate 33, and a stop pin 162 is carried by the opposite side of guide block 99 and extends into the path of travel of levers 97 and 88.

A ring 104 is fixedly secured to the adjacent side of plate 33, and carries spacing indicia thereon correlated with the point 101.

Interiorly of the flange ring 104 are positioned a pair of clamping shoes 166, each of which is provided with a projection 167, having an elongated slot 108 therein, which extends about the shaft 21. The clamping shoes are provided with elongated slots 110 through which extend screws 111, for securing the plates to disc 98.

Links 112 are pivotally connected at one of their ends 113 to each clamping shoe 106, and at their other ends are pivotally connected as by means of pivots 114 to a cross head 115 carried by set screw 1%. Thus, when pressure is applied by turning set screw 16% down tight in guide block 99, links 112 push shoes 1% outwardly to engage the interior of flange ring 104 with sufficient pressure to hold the space disc 98 with its stop pin 102 and indicator point 161 at the desired space setting on the indicia band 165. Releasing said screw 1% releases the pressure and pulls the shoes 106 inwardly allowing the space control disc to be freely rotated to other space settings.

In the use and operation of the device when it is desired to set the power head and employ the straight edge for ruling, the brake release lever 79 is first lifted with one hand and held, and the reset knob 61 is turned with the other to roll the carriage with the straight edge 59 to a desired starting position. The brake release lever 79 is then released to set the brake, thus preventing the carriage from rolling either way and holding the straight edge exactly in the desired position.

For setting the device to the appropriate spacing, the space control disc 93 is rotated with the stop pin 102 to a position where the indicator point 161 is at the right spacing mark on the indicator or indicia band 165. Set screw 1% is then tightened to hold stop pin 102 in its proper position. Levers 88, 97 and 79 are moved downwardly to the starting position. Now, employing the left hand the clutch lever 97 is held down with the thumb, and the brake release lever '79 is lifted a small amount with the ring finger to release the brake. At the same time the cam lever 38 is raised with the middle finger and index finger pressing tightly together the levers 88 and 97, thus tightening the clutch in Wheels 6 and 78. While the levers '97 and 88 are held clampingly between the fingers the clutch assembly is rotated to a point where clutch lever 97 contacts stop pin 162. This rotates the power wheel 96, to move the carriage with its straight edge 56 to the exact amount of space for which the control disc 98 is set. Simultaneously it rotates the brake release wheel 78 which maintains the brake in release position all during rotation of the clutch. When the appropriate setting is reached and pressure on levers 97 and $3 is released the spiral spring 82 rotates the brake release wheel 78 and its associated lever 79 back to its initial starting position resetting the brakes 7t) tightly against the interior of the flange 67'.

The straight line is now drawn, and the clutch operation is repeated for additional spacing. As many lines as desired may be thus drawn with the preset distance therebetween.

When a change in spacing is desired the spacing control cbiisfc 98 is reset and the clutch operation is repeated as e ore.

The carriage is returned to start position by turning the reset knob 66 with one hand while holding up the brake release lever 79 with the other. When the brake release lever 7 9 is released the brake is reset and the operation may be repeated as many times as desired.

From the foregoing it will now be seen that there is herein provided an improved variable spacing control which accomplishes all the objects of this invention, and others, including many advantages of great practical utility and commercial importance.

As many embodiments may be made in this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

I claim:

1. In a variable spacing control, the combination of a drafting board, a supporting frame secured to the underside of said drafting board, a track carried by said frame, a carriage movable in said track, a straight edge on said carriage extending across said drafting board, a transverse shaft rotatably mounted on said carriage, a pinion carried by said shaft, a rack carried by said frame engaged by said pinion, a power head mounted on said shaft, said power head including a knob for rotating said shaft to move said straight edge, adjustable means in said power head limiting said rotation of said shaft to a predetermined degree, means attached to said shaft for varying the adjustment of said last-mentioned means, said power head including a brake to lock said shaft against accidental rotation, a resetting knob controlling said means for varying the adjustment of said means limiting rotation of said shaft, a power wheel, and clutch means normally securing said power wheel to said shaft, means supported by said shaft for releasing said clutch means to permit independent rotation of said power disc about said shaft, and means operable to release said brake means upon actuation of said resetting means.

2. In a variable spacing control, the combination of a drafting board, a supporting frame secured to the underside of said drafting board, a track carried by said frame, a carriage movable in said track, a straight edge on said carriage extending across said drafting board, a transverse shaft rotatably mounted on said carriage, a pinion carried by said shaft, a rack carried by said frame engaged by said pinion, a power head mounted on said shaft, said power head including a knob for rotating said shaft to move said straight edge adjustable means in said power head limiting said rotation of said shaft to a predetermined degree, means attached to said shaft for varying the adjustment of said last-mentioned means, said power head including a brake to lock said shaft against accidental rotation, a resetting knob controlling said means for varying the adjustment of said means limiting rotation of said shaft, a power wheel and clutch means normally securing said power wheel to said shaft, means supported by said shaft for releasing said clutch means to permit independent rotation of said power disc about said shaft, means operable to release said brake means upon actuation of said resetting means, and spring means normally biasing said brake means into locking position.

3. In a variable spacing control, the combination of a drafting board, a supporting frame secured to the underside of said drafting board, a track carried by said frame, a carriage movable in said track, a straight edge on said carriage extending across said drafting board, a transverse shaft rotatably mounted on said carriage, a pinion carried by said shaft, a rack carried by said frame engaged by said pinion, a power head mounted on said shaft, said power head including a knob for rotating said shaft to move said straight edge, adjustable means in said power head limiting said rotation of said shaft to a predetermined degree, means attached to said shaft for varying the adjustment of said last-mentioned means, said power head including a brake to lock said shaft against accidental rotation, a resetting knob controlling said means for varying the adjustment of said means limiting rotation of said shaft, a power wheel and clutch means normally securing said power wheel to said shaft, means supported by said shaft for releasing said clutch means to permit independent rotation of said power disc about said shaft, means operable to release said brake means upon actuation of said resetting means, and spring means normally biasing said brake means into locking position, and additional spring means normally biasing said clutch into engaged position.

4. The structure of claim 3 wherein means are provided for adjusting said rack to align said carriage with said drafting board.

5. The structure of claim 3 wherein means are provided for limited angular variation of the position of said straight edge.

References Cited in the file of this patent UNITED STATES PATENTS 304,521 Gardam Sept. 2, 1884 1,288,871 Goodspeed Dec. 24, 1918 2,252,535 West et al. Aug. 12, 1941 2,399,610 West et al Apr. 30, 1946 2,558,468 Stovern June 26, 1951 2,577,159 Seferow Dec. 4, 1951 2,675,619 Cone Apr. 20, 1954 FOREIGN PATENTS 575,028 France Apr. 11, 1924 

1. IN A VARIABLE SPACING CONTROL, THE COMBINATION OF A DRAFTING BOARD, A SUPPORTING FRAME SECURED TO THE UNDERSIDE OF SAID DRAFTING BOARD, A TRACK CARRIED BY SAID FRAME, A CARRIAGE MOVABLE IN SAID TRACK, A STRAIGHT EDGE OF SAID CARRIAGE EXTENDING ACROSS SAID DRAFTING BOARD, A TRANSVERSE SHAFT ROTATABLY MOUNTED ON SAID CARRIAGE, A PINION CARRIED BY SAID SHAFT, A RACK CARRIED BY SAID FRAME ENGAGED BY SAID PINION, A POWER HEAD MOUNTED ON SAID SHAFT, SAID POWER HEAD INCLUDING A KNOB FOR ROTATING SAID SHAFT TO MOVE SAID STRAIGHT EDGE, ADJUSTABLE MEANS IN SAID POWER HEAD LIMITING SAID ROTATION OF SAID SHAFT TO A PREDETERMINED DEGREE, MEANS ATTACHED TO SAID SHAFT FOR VARYING THE ADJUSTMENT OF SAID LAST-MENTIONED MEANS, SAID POWER HEAD INCLUDING A BRAKE TO LOCK SAID SHAFT AGAINST ACCIDENTAL ROTATION, A RESETTING KNOB CONTROLLING SAID MEANS FOR VARYING THE ADJUSTMENT OF SAID MEANS LIMITING ROTATION OF SAID SHAFT, A POWER WHEEL, AND CLUTCH MEANS NORMALLY SECURING SAID POWER WHEEL TO SAID SHAFT, MEANS SUPPORTED BY SAID SHAFT FOR RELEASING SAID CLUTCH MEANS TO PERMIT INDEPENDENT ROTATION OF SAID POWER DISC ABOUT SAID SHAFT, AND MEANS OPERABLE TO RELEASE SAID BRAKE MEANS UPON ACTUATION OF SAID RESETTING MEANS. 